* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Poppins", sans-serif;
}

html,
body {
  /* background-color: #000000; */
  display: grid;
  height: 100%;
  place-items: center;
  overflow: hidden;
}

.btn-12 {
  position: relative;
  width: 300px;
  height: 95px;
  color: rgb(18, 190, 243);
  letter-spacing: 12px;
  font-size: 35px;
  line-height: 100px;
  text-align: center;
  text-transform: uppercase;
  user-select: none;
  text-decoration: none;
  overflow: hidden;
  /* box-shadow: inset 0 0 10px rgb(14, 20, 105), */
  /* 0 0 5px rgb(9, 208, 235); */
  transition: all 0.5s;
}

.btn-12:hover {
  text-shadow: 0 0 5px rgb(18, 190, 243), 0 0 8px rgb(18, 190, 243),
    0 0 10px rgb(18, 190, 243);

  /* box-shadow: inset 0 0 10px rgb(14, 20, 105),
            0 0 5px rgb(9, 208, 235),
            0 0 10px rgb(9, 208, 235); */
}

.btn-12 span {
  position: absolute;
}

.btn-12 span:nth-child(1) {
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-image: linear-gradient(to right, transparent, rgb(0, 153, 255));
  animation: move1 2s linear infinite;
}

@keyframes move1 {
  0% {
    transform: translateX(-100%);
  }

  100% {
    transform: translateX(100%);
  }
}

.btn-12 span:nth-child(2) {
  top: 0;
  right: 0;
  width: 2px;
  height: 100%;
  transform: translateY(-100%);
  background-image: linear-gradient(to bottom, transparent, rgb(0, 153, 255));
  animation: move2 2s linear infinite;
  animation-delay: 1s;
}

@keyframes move2 {
  100% {
    transform: translateY(100%);
  }
}

.btn-12 span:nth-child(3) {
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background-image: linear-gradient(to left, transparent, rgb(0, 153, 255));
  animation: move3 2s linear infinite;
}

@keyframes move3 {
  0% {
    transform: translateX(100%);
  }

  100% {
    transform: translateX(-100%);
  }
}

.btn-12 span:nth-child(4) {
  top: 0;
  left: 0;
  width: 2px;
  height: 100%;
  transform: translateY(100%);
  background-image: linear-gradient(to top, transparent, rgb(0, 153, 255));
  animation: move4 2s linear infinite;
  animation-delay: 1s;
}

@keyframes move4 {
  100% {
    transform: translateY(-100%);
  }
}
